One of the main objectives of change management in a computer network is to control the installation and updates to microcode and software application programs at multiple nodes from a central site through telecommunications lines which interconnect them to each other. Typical change management tasks include microcode engineering change and microcode fix distribution; configuration/customization data retrieval, manipulation and distribution; microcode engineering change installation, activation and removal controls; and status reporting for each function.
The central site processor is usually larger and more powerful than the processors at the remote nodes. Skilled data processing personnel are located at the central site, while the remote nodes usually run unattended. When changes have to be made, it is more practical to have them broadcast from the central site to the various distributed sites. Thus, the remote nodes are able to work independently from the host computer at the central site, while at the same time remaining connected to the host computer for file transfer and access to other applications.
In a typical network architecture such as the system network architecture (SNA) of IBM, a remote node called an entry point sends network management data about itself and the resources it controls to a central site called a focal point. Appropriate change management commands are issued from the focal point to the remote nodes. This change management in SNA is well documented in the prior art. For example, see the following: "Managing Changes in SNA Networks", IBM Systems Journal, Vol. 28, No. 2, pp. 260-273 (1989); "SNA Network Management Directions", IBM Systems Journal, Vol. 27, No. 1, pp. 3-14 (1988); and "System-Independent File Management and Distribution Services", IBM Systems Journal, Vol. 28, No. 2, pp. 241-259 (1989). However, in such prior art networks, it has not been practical to have multiple applications serviced by a single entry point. Instead, each application had its own entry point connected through at least one dedicated telecommunications line to a focal point node.
The specifications which describe the format and protocol for the GDS (general data stream) and for the related hierarchy of identifiers for SNA data objects is well known. For example, see "SNA: Format and Protocol Reference Manual: Management Services" SC30-3346; "SNA: Format and Protocol Reference Manual: File Services", SC31-6807; "SNA: Format and Protocol Reference Manual: Distribution Services", SC30-3098; and "SNA: Formats", GA27-3136 (See appendix A respecting description of GDS's). The problem was to utilize these known SNA protocols and formats in connection with SNA/DS, SNA/MS and SNA/FS without having to create all the software/hardware overhead required to establish an entry point for every application in the network.
A previous conventional entry point implementation for SNA was the IBM 3174 communications controller, which implemented a complete SNA solution using SNA/DS, SNA/MA and SNA/FS at the 3174 entry point. However, this previous implementation did not include any sub-entry points.